A Five-year Evaluation of the Silvicultural Treatments for the Control of Squirrel Damage in Taiwan

The Formosan red-bellied tree squirrel (Callosciurus erythraeus.) is a pest animal that causes serious damage to many conifer plantations in Taiwan. Poisoning has been the major means to control the damage. The feasibility of forestry control through habitat manipulation has been evaluated during the past 5 years. The objective of this study was to investigate the effects of forest-tending operations on the activity and damage by squirrels. Forest-tending conducted included weeding and thinning. Test sites were at three Japanese cedar (Cryptomeria japonica) plantations located in Chitou. The results of this study revealed that squirrel activity in the treated plots was greatly reduced. It was found that new damage done by the squirrels in treated areas was also reduced. This was particularly significant during an abnormal weather period when there was a continual rainstorm lasting for about 3 months. The treatments of weeding and thinning showed more significant effects on the reduction of squirrel activity than the reduction in the occurrence of new damages.